Electrical apparatus



Feb., 8,1927. c Q SMITH ELECTRICAL APPARATUS Filed May 5. 1921 l f l l l f ,l

mme?? Patented Feb. 8, 1927.

Unita tra? CHARLES C. SMITH, OP MEDPORD, MAssAOHUsETTa Assrenom BY MEsNE Assicu- MENTs, TO RAYTHEON MANUEACTURTNG COMPANY, or CAMBRIDGE, MASSACHU- sETTs, A CORPORATION oEMAssACHUsETTs.

ELECTRICAL APPARATUS.

Application tiled. May 3,

y The present invention relates to electrical apparatus and more particularly to the type of apparatus disclosed generally in the copending applications of Smith, Serial No. 415,536, filed October 8, 1920, and Serial No. 418,263, filed October'20, 1920.

In this type of apparatus cooperating elec-v trodes are immersed in' a gas and sodesigned and arranged with respect to one another that all available paths t'or conduction through the gas "are short and of the order of magnitude of the mean free path of the electrons and all paths through the insulating medium are suiiiciently long to prevent breakdown of the medium. v Such a construction may be employed as a rectifier of alternating currents by the introduction in the space between the electrodes of a magnetic field of suitable strength and direction.

It is the obj ect of the present invention to provide certain improvements in apparatus of this character tending to emphasize the characteristics which enable rectification to take place in' addition to enlarging the permissible range of magnetic field. With this Object in View it has been discovered that the cooperating electrodes may be so designed and located with respect to one another and to the lines of force of the magnetic field that there is a marked tendency to concentrate and localize the conduction in a well dened region.

In the accompanying drawings illustrating the preferred form of the invention Fig. 1 represents a sectional elevation of a tube embodying the principles of the invention; Fig. 2 is a section of the tube taken at right 'angles to Fig. 1; and Fig. 3 is a diagram- 'matic view illustrating a simple form of circuit in which the tube may be embodied as a rectifier.

The tube shown in the illustrated embodiment of the invention comprises the usual hermetically sealed receptacle 10 containing gas at the desired pressure. Re ceived within the receptacle and' immersed in the gas are cooperating electrodes 12 and 14 respectively. As will be observed from an inspection of the drawings, the cooperating electrodes are ring shaped, the outer electrode 14 having the form of a torus within which the inner electrode ring l2 is positioned concentrically. as will be self-evident. The outer electrode is conveniently formed trode member-,14 is 1921. Serial No. 466,517.

by two sheets 16 and 17 -of aluminum which are pressed into the shape indicated, clearly 1n Flg. 2, so that when joined the sheets cooperate to form the hollow circular tube 18'. The sheets are respectively provided with fins 19 and 20. Lugs 21 project alternately from the ns 19 and 20 and are adapted to be bent over the cooperating n to secure the sheets together. The outer elecrovided with a tubular neel: portion 24 which is rigidly connected at lts lower end to a supporting arm 25 clamped to the base 26 of the receptacle by a ring 27 forming a part of the arm and held 1n place by encircling wires 28. 1n

f addition, the outer elect-rode maybe steadied and supported by supporting members in the form of wires 40 and 42 which extend from projections 44 on the insulating base to a po1nt above the connection with the arm 25. The inner electrode 12 may consist of a copperv or aluminum rod of circular cross section bent into a ring form, as indicated in Fig. 1` and having a straight supportin portion 30 which is mounted at the en opposlte the electrode in the upper end 32 of the insulator base 26, the construction (Y above described serving to maintain the inner and outer electrode'members in the desired positions with relation to one another. The inner electrode member 12 may be connected with a lead, indicated at 50, and the outer electrode is connected with a lead 52, which passes through the wall of the base 26 and is connected to the outside of the` neck portion 24. as indicated clearly in Fig. 2.

A magnetic field having the linesof force substantially straight and extending transversely of the tube in a direction substantially normal to the plane offth electrodes may be conveniently introduced in the space separating the electrodes by a permanent magnet arranged as indicated more particularly in Fig. 2 with the opposite poles positioned in close proximity to the fiattened sides of the tube, the magnet being indicated at 54. 1n the illustrated embodiment of the invention and with a magnetic iield of the type described introduced between the electrodes the tube may be caused to freely conduct when the outer electrode is negative and acts as a cathode and to insulate against conduction when the inner electrode is negative and acts as the cathode. The discharge,

til

,region 'is believed to be caused b v the tendency of the magnetic field in conjunction with the curvature of the electrode surfaces to divert the paths of electrons which start in a region removed from the plane toward the plane. Owing to this diversion of the paths of the electrons the new electrons are constant-ly liberated at points-nearer the plane so that eventually the region of greatest intensity of discharge is immediately adjacent to the plane. The advantage of a construction which unctons in the above described manner is primarily due to the fact that it greatly enlarges the permissible range of magnetic field over which rectification may take place.

The tube obviously may be embodied in a variety of circuits one of which is indicated in Fig. 3, this figure indicatinga simple form of circuit embodying the tube as a rectifier. As shown in the figure. an input circuit 60 is provided with a suitable source of alternating current 62, this input circuit being connected with the tube circuit (Si through a step-up transformer 66 to deliver alternating current of high potential to the tube indicated at 10.

I claim:

1. An electrical apparatus comprising a hollow tubular electrode of circular shape, an inner electrode ring supported concentrically therewith, means for creating an electric field in the space between the electrodes, and means for introducing a magnetic field between the electrodes with the lines of force extending in a direction substantially normal to the plane of the electrodes.

2. An electrical apparatus comprising toroidal electrodes supported in concentric relation and immersed in a gas., mea-ns for creating a radial electric field in the space n separating theelectrodes, and means for introducing a magnetlc field with the lines of force extending substantially normal to the plane of the electrodes.

3. An electrical apparatus comprising a hollow crcular electrode having aA tubular neck portion7 an electrode ring supported in thchollow electrode and having a stem,

an insulator base connected with the stein to support the ring 1n concentric relation to `the outer electrode, connections between the\ base and the tubular neck of the outer electrode, and 'leads connected respectively with 00 the inner and outer electrodes.

4. An electric apparatus comprising a gas filled receptacle, a curved electrode immersed therein, a second curved tubular electrode surrounding the first electrode, with the lon- 55 gitudinal curved axis of the first electrode lying inside the cross-sectional outline of the tubular electrode, both electrodes lying slibstantially 1n a plane, and means for 11npressing a substantially straight magnetic 70 bular elect-rode immersed in a gas and having opposing surfaces spaced apart adistance comparable to the mean free path of electrons in the gas, means forapplying a potential difference between the electrodes,

and means for impressing a magnetic field in a direction substantially perpendicular to the axis of the electrodes.

6. An electrical apparatus comprising internal andy external toroidal electrodes,

means for impressing an electric fieldv between the electrodes, and means for impressing a magnetic field normal to the plane of the electrodes.

CHARLES o. SMITH. 

